Moller, Anders Pape; Hoglund, Jacob (1991). Patterns of Fluctuating Asymmetry in Avian Feather Ornaments: Implications for Models of Sexual Selection. Proceedings: Biological Sciences. 245. [S.l.: s.n.] pp. 1–5. doi:10.1098/rspb.1991.0080
Hickman, Scott (2008), «The trouble with tertials», Auk, 125 (2): 493, doi:10.1525/auk.2008.2408